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991.
Yoshio Shimabukuro Hiroaki Terashima Masahide Takedachi Kenichiro Maeda Tomomi Nakamura Keigo Sawada Mariko Kobashi Toshihito Awata Hiroyuki Oohara Takanobu Kawahara Tomoaki Iwayama Tomoko Hashikawa Manabu Yanagita Satoru Yamada Shinya Murakami 《Journal of cellular physiology》2011,226(3):809-821
Fibroblast growth factor‐2 (FGF‐2) regulates a variety of functions of the periodontal ligament (PDL) cell, which is a key player during tissue regeneration following periodontal tissue breakdown by periodontal disease. In this study, we investigated the effects of FGF‐2 on the cell migration and related signaling pathways of MPDL22, a mouse PDL cell clone. FGF‐2 activated the migration of MPDL22 cells and phosphorylation of phosphatidylinositol 3‐kinase (PI3K) and akt. The P13K inhibitors, Wortmannin and LY294002, suppressed both cell migration and akt activation in MPDL22, suggesting that the PI3K/akt pathway is involved in FGF‐2‐stimulated migration of MPDL22 cells. Moreover, in response to FGF‐2, MPDL22 showed increased CD44 expression, avidity to hyaluronan (HA) partly via CD44, HA production and mRNA expression of HA synthase (Has)‐1, 2, and 3. However, the distribution of HA molecular mass produced by MPDL22 was not altered by FGF‐2 stimulation. Treatment of transwell membrane with HA facilitated the migration of MPDL22 cells and an anti‐CD44 neutralizing antibody inhibited it. Interestingly, the expression of CD44 was colocalized with HA on the migrating cells when stimulated with FGF‐2. Furthermore, an anti‐CD44 antibody and small interfering RNA for CD44 significantly decreased the FGF‐2‐induced migration of MPDL22 cells. Taken together, PI3K/akt and CD44/HA signaling pathways are responsible for FGF‐2‐mediated cell motility of PDL cells, suggesting that FGF‐2 accelerates periodontal regeneration by regulating the cellular functions including migration, proliferation and modulation of extracellular matrix production. J. Cell. Physiol. 226: 809–821, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
992.
Sato K Kawamura A Obara T Kawai S Kajita S Kitano H Katayama Y 《Plant cell reports》2011,30(12):2195-2205
Rice internodes must have the proper shape to support high-yielding panicles. The shape of internodes is controlled by various
factors involved in their formation, such as developmental patterns, cell division, cell elongation, and cell wall biosynthesis.
To understand the regulation of internode development, we screened dwarf mutants to identify those with a phenotype of ectopic
deposits of phenolic components in parenchyma cell walls of internodes. We named these mutants ectopic deposition of phenolic components1 (edp1). Two alleles were identified, edp1-1 and edp1-2. Furthermore, these mutants showed disordered cell files in internode parenchyma. These abnormal phenotypes were very similar
to that of a previously reported dwarf50 (d50) mutant. Genetic analyses of edp1 mutants revealed that the edp1 loci are distinct from d50. Our results indicate that analyses of edp1 mutants as well as the d50 mutant will be useful for understanding the molecular mechanisms behind ectopic deposition of cell wall phenolic components
in internode parenchyma cells and the regulation of internode development. 相似文献
993.
Watanabe H Ono M Kimura H Kagawa S Nishii R Fuchigami T Haratake M Nakayama M Saji H 《Bioorganic & medicinal chemistry letters》2011,21(21):6519-6522
We report a fluorinated and iodinated radiotracer as a probe for PET/SPECT to detect of β-amyloid (Aβ) plaques in the brain of patients with Alzheimer's disease (AD). We successfully designed and synthesized the fluorinated and iodinated aurone derivative (3) and its radiolabels ([(125)I]3 and [(18)F]3). In binding experiments in vitro, 3 showed high affinity for Aβ aggregates (K(i)=6.81nM). In brain sections of AD model mice, 3 intensely stained Aβ plaques. Furthermore, a specific plaque labeling signal was observed on the autoradiography of postmortem AD brain sections using [(125)I]3. In biodistribution experiments using normal mice, [(125)I]3 and [(18)F]3 displayed good uptake into and a rapid washout from the brain, properties highly desirable for Aβ imaging agents. These results suggest that 3 may function as a PET/SPECT dual imaging agent for detecting Aβ plaques in AD brains. 相似文献
994.
Sejima E Yamauchi A Nishioku T Koga M Nakagama K Dohgu S Futagami K Kataoka Y 《Cellular and molecular neurobiology》2011,31(7):985-989
Olanzapine is known to be advantageous with respect to outcome and drug compliance in patients with schizophrenia. However,
olanzapine has adverse effects, including a higher incidence of weight gain and metabolic disturbances, when compared with
those of other antipsychotic agents. The mechanisms underlying these adverse events remain obscure. Female rats were orally
administered olanzapine (2 mg/kg) or vehicle once a day for 2 weeks to ascertain if hypothalamic AMP-activated protein kinase
(AMPK) mediates olanzapine-induced weight gain and hyperphagia. Body weight and food intake in each rat were evaluated every
day and every two days, respectively. After the termination of drug treatment, we measured the protein levels of AMPK and
phosphorylated AMPK in the hypothalamus using western blot analyses. Olanzapine significantly increased body weight and food
intake. The phosphorylation levels of AMPK were significantly elevated by olanzapine. These results suggest that activation
of hypothalamic AMPK may mediate hyperphagia and weight gain induced by chronic treatment with olanzapine. 相似文献
995.
996.
Ueda T Shikano M Kamiya T Joh T Ugawa S 《American journal of physiology. Gastrointestinal and liver physiology》2011,301(1):G138-G147
The esophageal epithelium has sensory properties that enable it to sustain normal barrier function. Transient receptor potential vanilloid 4 (TRPV4) is a Ca(2+)-permeable channel that is activated by extracellular hypotonicity, polyunsaturated fatty acids, phorbol esters, and elevated temperature. We found that TRPV4 is expressed in both human esophageal tissue and in HET-1A cells, a human esophageal epithelial cell line. Specific activation of TRPV4 by the phorbol ester 4α-phorbol 12,13-didecanoate (4α-PDD) increased intracellular Ca(2+) in a subset of HET-1A cells. Elevated temperature strongly potentiated this effect at low concentrations of 4α-PDD, and all of the responses were inhibited by the TRPV antagonist ruthenium red. TRPV4 activation differentially affected cell proliferation and cell viability; HET-1A cell proliferation was increased by 1 μM 4α-PDD, whereas higher concentrations (10 μM and 30 μM) significantly decreased cell viability. Transient TRPV4 activation triggered ATP release in a concentration-dependent manner via gap-junction hemichannels, including pannexin 1 and connexin 43. Furthermore, TRPV4 activation for 24 h did not increase the production of interleukin 8 (IL-8) but reduced IL-1β-induced IL-8 production. Small-interference RNA targeted to TRPV4 significantly attenuated all of the 4α-PDD-induced responses in HET-1A cells. Collectively, these findings suggest that TRPV4 is a novel regulator of Ca(2+)-dependent signaling pathways linked to cell proliferation, cell survival, ATP release, and IL-8 production in human esophageal epithelial cells. 相似文献
997.
Tanamura K Abe T Kamimura N Kasai D Hishiyama S Otsuka Y Nakamura M Kajita S Katayama Y Fukuda M Masai E 《Bioscience, biotechnology, and biochemistry》2011,75(12):2404-2407
The glutathione S-transferases, LigF and LigE, of Sphingobium sp. strain SYK-6 respectively play a role in cleavage of the β-aryl ether of (+)-(βS)-α-(2-methoxyphenoxy)-β-hydroxypropiovanillone (MPHPV) and (-)-(βR)-MPHPV. The ligP gene, which showed 59% similarity to ligE at the amino acid level, was isolated from SYK-6. LigP produced in Escherichia coli revealed enantioselectivity for (-)-(βR)-MPHPV, and ligE and ligP alone contributed to the degradation of (-)-(βR)-MPHPV in SYK-6. 相似文献
998.
999.
Hui Shen Atsuya Yamashita Masamichi Nakakoshi Hiromasa Yokoe Masashi Sudo Hirotake Kasai Tomohisa Tanaka Yuusuke Fujimoto Masanori Ikeda Nobuyuki Kato Naoya Sakamoto Hiroko Shindo Shinya Maekawa Nobuyuki Enomoto Masayoshi Tsubuki Kohji Moriishi 《PloS one》2013,8(12)
Caffeic acid phenethyl ester (CAPE) has been reported as a multifunctional compound. In this report, we tested the effect of CAPE and its derivatives on hepatitis C virus (HCV) replication in order to develop an effective anti-HCV compound. CAPE and CAPE derivatives exhibited anti-HCV activity against an HCV replicon cell line of genotype 1b with EC50 values in a range from 1.0 to 109.6 µM. Analyses of chemical structure and antiviral activity suggested that the length of the n-alkyl side chain and catechol moiety are responsible for the anti-HCV activity of these compounds. Caffeic acid n-octyl ester exhibited the highest anti-HCV activity among the tested derivatives with an EC50 value of 1.0 µM and an SI value of 63.1 by using the replicon cell line derived from genotype 1b strain Con1. Treatment with caffeic acid n-octyl ester inhibited HCV replication of genotype 2a at a similar level to that of genotype 1b irrespectively of interferon signaling. Caffeic acid n-octyl ester could synergistically enhance the anti-HCV activities of interferon-alpha 2b, daclatasvir, and VX-222, but neither telaprevir nor danoprevir. These results suggest that caffeic acid n-octyl ester is a potential candidate for novel anti-HCV chemotherapy drugs. 相似文献
1000.